"Any Republican who has a good record, who makes the case that it's time for an era of conservative change, who aggressively goes after her record and aggressively dissects her foreign policy record is going to have a very good chance,'' Rubin, author of the "Right Turn" blog, told "The Steve Malzberg Show" on Newsmax TV.

"If you have a good, solid candidate with a clear message, that person can beat Hillary Clinton," she said Monday.

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Rubin said Republican strategist Karl Rove was correct in raising the issue of the former secretary of state's health after a serious blood clot that hospitalized her five years ago.

"Absolutely, the woman was down for the count for six months, according to her husband. She will be 69 years old when she runs for president," Rubin said.

She said the "outraged rebels" who blasted Rove for raising the health issue once questioned John McCain's mental stability. "So, the mock outrage that anyone should question Queen Hillary is just a little bit much to take," she said.

Rubin said Clinton's "real problem'' is not that she's "a tired old lady'' but rather that she has "tired old lady ideas.''

"Her views haven't changed and her ideas haven't changed since the 1960s and the '70s,'' Rubin said.